package com.idrem.util;

public class DistanceTool {
	
	public static double gps2m(double lat_a, double lng_a, double lat_b, double lng_b) {
		   double EARTH_RADIUS = 6378137.0;  
	       double radLat1 = (lat_a * Math.PI / 180.0);
	       double radLat2 = (lat_b * Math.PI / 180.0);
	       double a = radLat1 - radLat2;
	       double b = (lng_a - lng_b) * Math.PI / 180.0;
	       double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2)
	              + Math.cos(radLat1) * Math.cos(radLat2)
	              * Math.pow(Math.sin(b / 2), 2)));
	       s = s * EARTH_RADIUS;
	       s = Math.round(s * 10000) / 10000;
	       return s;
	    }

}
